Arrangement for assembling two groups of components in a predetermined relative position

ABSTRACT

An electromagnet has a yoke with an attaching portion fitting into a guideway in a mounting plate and projecting from the rear face of the plate, a U-shaped leaf spring is mounted in recesses of the mounting plate and engages pins projecting from the attaching portion to hold the electromagnet on the front face of the mounting plate. When a second mounting plate, forming part of another device, is secured to the rear face of the first mounting plate, the attaching portion is resiliently pushed to a position flush with the rear face of the first mounting plate so that the electromagnet is placed in the correct relative position to the other device due to the fact that the position of the electromagnet is determined by the face of the second mounting plate.

Hanenkamp et a].

11 3,735,304 [451 May 22,1973

ARRANGEMENT FOR ASSEMBLING TWO GROUPS OF COMPONENTS IN A PREDETERMINED RELATIVE POSITION Inventors: Horst Hanenkamp, l-leidmuhle; Helmut Wolken-Mohlmann, Esens, both of Germany Olympia Werke helmshaven, Germany Filed: May 12, 1972 Appl. No.: 252,677

Assignee: A.G., Wil- Int. Cl. ..I-I0lf 7/00 Field of Search ..335/278, 276, 281

References Cited UNITED STATES PATENTS 5/1948 Biggle ..335/276 2,585,684 2/1952 Roggenstein ..335/276 X Primary ExaminerGeorge Harris Attorney-Michael S. Striker [57] ABSTRACT An electromagnet has a yoke with an attaching portion fitting into a guideway in a mounting plate and projecting from the rear face of the plate, a U-shaped leaf spring is mounted in recesses of the mounting plate and engages pins projecting from the attaching portion to hold the electromagnet on the front face of the mounting plate. When a second mounting plate, forming part of another device, is secured to the rear face of the first mounting plate, the attaching portion is resiliently pushed to a position flush with the rear face of the first mounting plate so that the electromagnet is placed in the correct relative position to the other device due to the fact that the position of the electromagnet is determined by the face of the second mounting plate.

10 Claims, 6 Drawing Figures Patented May 22, 1973 4 Sheets-Sheet 1 Patented May 22, 1973 3,735,3(M

4 sheets sheet 2 II I] i: :p

FIG.2

Patented May 22, 1973 4 Shets-Sheet 3 Patented May 22, 1973 3,735,304

4 Sheets-Sheet "4 ARRANGEMENT FOR ASSEMBLING TWO GROUPS OF COMPONENTS IN A PREDETERMINED RELATIVE POSITION BACKGROUND OF THE INVENTION It is known to secure a component, such as an electromagnet, to the front face of a mounting plate by a pin passing through an attaching portion of the component, and being located on the rear face of the mounting plate. This type of mounting has the advantage of an easy assembly, but has certain disadvantages inasmuch as it is difficult to mount the electromagnet or other component, in an exactly correct position relative to an other component or device.

For example, in an electric typewriter, groups of components are separately assembled, and the assembled groups have to be then assembled in an exactly determined relative position. Generally, such a group of components includes a mounting plate consisting of an insulating material, and having a printed circuit thereon, and also carrying other devices, such as an electromagnet. When an electromagnet mounted on a mounting plate is to be used for operating mechanical elements, for example couplings, it is necessary that the electromagnets after assembly on the respective mounting plate have armatures which are precisely positioned to cooperate with other groups of components separately assembled on another mounting plate. Precision is particularly required if the electromagnets are to operate at high speed, as is, for example, required in adding devices for the printing means, or coupling devices for punches, which require very small magnets which have a correspondingly small stroke of the armature.

It is a disadvantage of the prior art that the mounting plates which consist of an insulating material, have no great stability or rigidity. Consequently, when the mounting plates of two different groups of components consisting of more rigid materials, are secured to each other, the required tolerances for cooperation of the devices carried by the respective mounting plates, such as the magnet armature or coupling elements, cannot be assured. This disadvantage cannot even be corrected by adjusting means since the insulating mounting plate warp when heated by the respective electric devices during operation of the apparatus.

SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of the mounting arrangements according to the prior art, and to provide an arrangement for assembling at least two groups of components in a predetermined relative position in which certain components accurately cooperate with each other.

An other object of the invention is to control the position of a first group of components mounted on a first mounting plate, by the position of the mounting plate of a second group of components.

Another object of the invention is to position a first group of components on a flexible mounting plate in such a manner that the components are in an exactly determined position to other components mounted on an other mounting plate.

With these objects in view, the present invention provides a first device, such as an electromagnet, with an attaching portion slidingly fitting into a guideway in the mounting plate, and having in the direction of insertion, such a length that the attaching portion projects slightly from the rear face of the mounting plate. The attaching portion is secured to the mounting plate by a spring by which, when the mounting plate of another group of components is secured to the first mounting plate in a position abutting the rear face thereof, the position of the first device is accurately determined in relation to the devices carried by the second mounting plate.

In this manner the result is obtained that a first device resiliently mounted on a first mounting plate, is held by the action of the spring against a guide face of a second mounting plate which assures the exact relative position of the first device to the second device even if the mounting plate has been deformed by the effect of heat or mechanical forces.

An embodiment of the invention comprises a first group of components including a mounting plate having a guideway, and a first device located on the front face of the first mounting plate and having an attaching portion fitting into the guideway in a direction transverse to the front face to an attaching position, the attaching portion being longer than the guideway and having a portion projecting in the attaching position from the rear face of the mounting plate; spring means located between the first device and the first mounting plate slidable to a holding position passing over a holding part, such as transverse pins, of the attaching portion, and being anchored by the first mounting plate for resiliently holding the first device in the attaching position; a second group of components including a second mounting plate, and a second device fixedly mounted on the second mounting plate; and means securing the second mounting plate to the first mounting plate in a position abutting the rear face of the mounting plate so that the projecting portion of the attaching means is pressed against the action of the spring means to a position flush with the rear face of the first mounting plate so that the spring means is tensioned and firmly holds the first device on the first mounting plate in a position for cooperating with the second device.

In the preferred embodiment of the invention, the mounting plate of the first device has recesses bounded by guide faces which form a gap for the insertion of a leaf spring. The recesses are formed alternately in the front face and in the rear face of the mounting plate, and also on opposite sides of the guideway so that the spring means can be constructed as a U-shaped leaf spring.

In such an arrangement, the holding leaf spring is located within the mounting plate when the first group of components is assembled. This has the advantage that the spring does not project anywhere from the front and rear faces of the mounting plate, and that the guide faces hold the leaf spring against movement in opposite directions.

Preferably, the first device has a pair of pins laterally projecting from opposite sides of the attaching portion, and located in a deep recess, only slightly projecting from the deep recess due to a corresponding diameter. Such a construction obtains the result that the first device, such as an electromagnet, resiliently abuts with pretension on the face of the second mounting plate.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation,

together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary perspective exploded view illustrating a first group of components in accordance with a first embodiment of the invention;

FIG. 2 is a longitudinal sectional view illustrating the embodiment of FIG. 1 together with a second group of components;

FIG. 3 is a plan view illustrating the front face of the mounting plate of the first group of components;

FIG. 4 is a bottom view illustrating the rear face of the mounting plate of FIG. 3;

FIG. 5 is a longitudinal sectional view of the mounting plate shown in FIGS. 3 and 4; and

FIG. 6 is a cross sectional view taken on line VIVI in FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a first group of components, including a first device 1, shown to be an electromagnet whose rectangular yoke 3 has an attaching portion slidingly fitting into a guideway 4 in a mounting plate 5. FIG. 1 shows that the electromagnet 1 can be inserted into the guideway in a direction transverse to the mounting plate 5. A slide fit is provided between the attaching portion of yoke 3 and the walls of guideway or slot 4, so that the electromagnet 1 can be easily inserted into the slot. When the attaching portion of yoke 3 is fully inserted, it slightly projects from the rear face of the mounting plate 5.

The front face and rear face of the mounting plate 5 are formed with recesses, as best seen in FIGS. 3 to 5. The front face has two rectangular recesses 6 located on opposite sides of the guideway or slot 4, and being bounded by guide face portions 6b of guide portions 6a of the mounting plate, as best seen in FIG. 5.

The rear face of the mounting plate 5 has a first recess 8, bounded by a rearward facing face 8b of a portion 8a of mounting plate 5, and a pair of recesses 7, located on opposite sides of the guideway 4 and being bounded by slanted guide face portions 7a of two guide portions 7b. The rearmost guide face portions 8b and 7b, and the foremost guide faces 6b of guide portions 60 are located in parallel planes to form a gap 9 for the insertion of a U-shaped leaf spring 10, best seen in FIG. 1. Leaf spring 10 has a pair of legs 11 and 12, and when leaf spring 10 is inserted in the direction of arrow 9c in FIG. 5 into the gap 9, the leaf spring 10 can be pushed to the position shown in chain lines in FIG. 5, in which the yoke portion of the leaf spring resiliently engages the guide face portion 8b, the center portions of the legs 11 and 12 engage the guide face portions 6b, and the ends of the legs 11, 12 are located under and resiliently engage the guide face portion 7b.

The guide portion 6a of mounting plate 5 has a shoulder 6c with an abutment face 14 on both sides of guideway 4. The electromagnet 1 has holding pins 13 projecting in opposite directions from the attaching portion 3, and the abutment faces 14 are so located that pins 13 rest thereon when pressed down by the action of the leaf spring 10.

The diameter of pins 13 is slightly greater than the depth of the shoulder so that the legs 11 and 12 of spring 10 act on the pins 13 when the ends of the legs 11, 12 are pushed under the guide face portions 7b.

The slanted and slightly curved guide faces 7b facilitate the insertion of the leaf spring 10 from the left as viewed in FIG. 5 after the attaching portion 3 has been placed in the guideway 4 and inserted until pins 13 abut the abutment faces 14. In this condition, the lowermost portion of attaching portion 3 projects slightly from the rear face of the mounting plate 5.

The transverse spacing between the legs 11, 12 of leaf spring 10 corresponds to the thickness of the attaching portion 3 formed by the yoke 2 so that legs 1 1, 12 are located on opposite sides of the guideway 4 for engatement with pins 13.

When the electromagnet 1 is moved downward in a direction perpendicular to the mounting plate 5, its attaching portion 3 enters the guideway 4, sliding on the surfaces thereof, and when the pins 13 abut the abutment faces 14 of the shoulders 6c of the guide portions 6a on opposite sides of the attaching portion 3, the lower edge of attaching portion 3 slightly projects from the rear face of mounting plate 5.

In this position, the leaf spring 10 is inserted into gap 9, with the leading end thereof guided by the slanted and curved rearward facing guide face portions 7b. Due to the fact that the diameter of the pins 13 is greater than the depth of the shoulders 6c, spring 10 is pretensioned, and resiliently holds the electromagnet l on the front face of mounting plate 5. Due to the resilient tension applied to spring 10 in gap 9 by pins 13, leaf spring 10 is securely anchored in the mounting plate 5, and cannot drop out.

If the group of components including the first electromagnetic device 1 and the mounting plate 5, is to be secured to another group of components 16 which includes a second mounting plate 19, the portion of the attaching portion 3 which slightly projects from the rear face of mounting plate 5, is placed on the face 15 of the second mounting plate 19. Thereupon, screws 20 are inserted into stepped bores 20a in mounting plate 5 and threaded into threaded bores 20b in the second mounting plate 19, so that the abutment face 15 of the second mounting plate 19 firmly abuts the rear face of mounting plate 15, which requires upward displacement of the attaching portion 3 together with electromagnet 1 until the bottom face of the attaching portion 3 is flush with the rear face of the mounting plate 5. This displacement of the electromagnet 1 requires a stressing of leaf spring 10 by the pins 13. The increased spring force causes a firm abutment of the attaching portion 3 of the electromagnet 1 on the abutment face 15 of the second mounting plate 19 so that the electromagnet 1, or other corresponding device, is exactly positioned in relation to the abutment face 15, which is part of the second group of components 16. Consequently, the armature 1a is always exactly positioned in relation to a lever 17 which cooperates with an oscillating element 18 also belonging to the second group of components 16. Plate 19 carries a post 22 secured by a screw 23 to a supporting plate 24 on which the oscillating means 18 is mounted in a manner which is not an object of the invention.

The precise relative position between first and second components 1a and 17 is maintained even if mounting plate 5, which may be an insulating plate carrying a printed circuit, is warped by heat or mechanical forces during operation. In all positions of the mounting plate 5, the spring holds the attaching portion 3 of the device 1 in abutment with the surface of the group of components 16 so that the position of the electromagnet 1 does not depend on the position of the mounting plate 5, but on the position of the abutment face 15 which is engaged by the bottom face of the attaching portion 3.

Due to the fact that the gap 9 in mounting plate 5 is formed by recesses 7 and 8 in the rear face, and recess 6 in the front face of the mounting plate 5, the leaf spring 10 is located within the mounting plate 5 so that the front and rear faces of mounting plate 5 are not interrupted and can be placed in contact with other planar surfaces.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of arrangements for assembling two groups of components differing from the types described above.

While the invention has been illustrated and described as embodied in an arrangement for assembling two groups of components in a predetermined relative position with one group of components in resilient engagement with the other group of components, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. Arrangement for assembling two groups of components in a predetermined relative position, comprising a first group of components including a first mounting plate having a guideway, a first device located on the front face of said first mounting plate and having an attaching portion fitting into said guideway for insertion in a direction transverse to said front face to an attaching position, said attaching portion being longer in said direction than said guideway and having a portion projecting in said attaching position from the rear face of said first mounting plate; said attaching portion having at least one holding part, and spring means located between said first device and said first mounting plate slidable to a holding position passing over said holding part of said attaching portion, and being anchored in said first mounting plate for resiliently holding said first device in said attaching position; a second group of components including a second mounting plate, and a second device fixedly mounted on said second mounting plate; and means securing said second mounting plate to said first mounting plate in a position abutting said rear face of said first mounting plate so that said projecting portion of said attaching means is pressed against the action of said spring means to a position flush with said rear face so that said spring means is tensioned and firmly holds said first device on said first mounting plate in a position for cooperating with said second device.

2. Arrangement as claimed in claim 1 wherein said guideway is an elongated slot into which said attaching portion slidingly fits; wherein said holding part includes aligned pins projecting in opposite directions from said attaching portion; and wherein said spring means has two legs, the ends of said legs being anchored in said first mounting plate and said legs being located on opposite sides of said attaching portion passing over said pins.

3. Arrangement as claimed in claim 1 wherein said first mounting plate has in said rear face first and second recesses bounded by first and second rearward facing guide faces, and has in said front face a third recess bounded by a third forward facing guide face located between said first and second guide faces, said first and second guide faces, and said third guide face being located in parallel planes so as to form a narrow gap for said leaf spring means; and wherein said spring means is a leaf spring means having ends resiliently abutting said first and second guide faces, respectively, and a central portion guided on said third guide face, and passing forwardly over said holding part of said attaching means.

4. Arrangement as claimed in claim 3 wherein said second guide face includes two second guide face portions located on opposite sides of said guideway; wherein said third guide face includes two third guide face portions located on opposite sides of said guideway; wherein said holding part of said attaching means includes two aligned pins projecting in opposite directions from said attaching portion; and wherein said leaf spring means has one end abutting said first guide face, and a pair of legs passing over said pins, respectively, said legs having ends resiliently abutting said second guide face portions, respectively.

5. Arrangement as claimed in claim 4 wherein said two third guide faces have forward facing rearward depressed shoulder portions on which said pins abut, said pins having a diameter slightly greater than the depth of said depressed shoulder portions so that said pins project slightly from the adjacent third guide face portions.

6. Arrangement as claimed in claim 4 wherein said leaf spring means is U-shaped and has a yoke portion abutting said first guide face, and leg end portions resiliently abutting said second guide face portions.

7. Arrangement as claimed in claim 4 wherein said second guide face portions are slanted for guiding the leading ends of said legs of said leaf spring means to facilitate insertion of said leaf spring means into said gap.

8. Arrangement as claimed in claim 1 wherein said first device is an electromagnet having a yoke including said attaching portion.

9. Arrangement as claimed in claim 8 wherein said attaching portion is elongated and has parallel lateral faces slidingly fitting into said guideway.

10. Arrangement as claimed in claim 9 wherein said attaching portion has laterally projecting pins constituting said holding part and engaged by said leaf spring means. 

1. Arrangement for assembling two groups of components in a predetermined relative position, comprising a first group of components including a first mounting plate having a guideway, a first device located on the front face of said first mounting plate and having an attaching portion fitting into said guideway for insertion in a direction transverse to said front face to an attaching position, said attaching portion being longer in said direction than said guideway and having a portion projecting in said attaching position from the rear face of said first mounting plate; said attaching portion having at least one holding part, and spring means located between said first device and said first mounting plate slidable to a holding position passing over said holding part of said attaching portion, and being anchored in said first mounting plate for resiliently holding said first device in said attaching position; a second group of components including a second mounting plate, and a second device fixedly mounted on said second mounting plate; and means securing said second mounting plate to said first mounting plate in a position abutting said rear face of said first mounting plate so that said projecting portion of said attaching means is pressed against the action of said spring means to a position flush with said rear face so that said spring means is tensioned and firmly holds said first device on said first mounting plate in a position for cooperating with said second device.
 2. Arrangement as claimed in claim 1 wherein said guideway is an elongated slot into which said attaching portion slidingly fits; wherein said holding part includes aligned pins projecting in opposite directions from said attaching portion; and wherein said spring means has two legs, the ends of said legs being anchored in said first mounting plate and said legs being located on opposite sides of said attaching portion passing over said pins.
 3. Arrangement as claimed in claim 1 wherein said first mounting plate has in said rear face first and second recesses bounded by first and second rearward facing guide faces, and has in said front face a third recess bounded by a third forward facing guide face located between said first and second guide faces, said first and second guide faces, and said third guide face being located in parallel planes so as to form a narrow gap for said leaf spring means; and wherein said spring means is a leaf spring means having ends resiliently abutting said first and second guide faces, respectively, and a central portion guided on said third guide face, and passing forwardly over said holding part of said attaching means.
 4. Arrangement as claimed in claim 3 wherein said second guide face includes two second guide face portions located on opposite sides of said guideway; wherein said third guide face includes two third guide face portions located on opposite sides of said guideway; wherein said holding part of said attaching means includes two aligned pins projecting in opposite directions from said attaching portion; and wherein said leaf spring means hAs one end abutting said first guide face, and a pair of legs passing over said pins, respectively, said legs having ends resiliently abutting said second guide face portions, respectively.
 5. Arrangement as claimed in claim 4 wherein said two third guide faces have forward facing rearward depressed shoulder portions on which said pins abut, said pins having a diameter slightly greater than the depth of said depressed shoulder portions so that said pins project slightly from the adjacent third guide face portions.
 6. Arrangement as claimed in claim 4 wherein said leaf spring means is U-shaped and has a yoke portion abutting said first guide face, and leg end portions resiliently abutting said second guide face portions.
 7. Arrangement as claimed in claim 4 wherein said second guide face portions are slanted for guiding the leading ends of said legs of said leaf spring means to facilitate insertion of said leaf spring means into said gap.
 8. Arrangement as claimed in claim 1 wherein said first device is an electromagnet having a yoke including said attaching portion.
 9. Arrangement as claimed in claim 8 wherein said attaching portion is elongated and has parallel lateral faces slidingly fitting into said guideway.
 10. Arrangement as claimed in claim 9 wherein said attaching portion has laterally projecting pins constituting said holding part and engaged by said leaf spring means. 